The diagnostic access to diseases of the intestine is subjected to constant change as a consequence of advances in medical technology.
Endoscopic methods for a long time constituted the standard for intestinal diagnostics. Since, because of their invasive nature, the endoscopic methods are rejected by a portion of the patients, in particular as regards preventive diagnostics, non-invasive diagnostic methods based on imaging are currently becoming established.
Modern radiological sectional imaging methods such as computed tomography and NMR tomography for acquiring appropriate tomography data records (single slice data records or volume data records) and reconstruction methods based on these data enable non-invasive diagnostic techniques, for example of the intestine.
It is known to display such tomography data graphically in various ways. For example, the following forms of display are known for tomography data:
The classic view in the transverse 2D reconstruction.
A volume rendering mode as 3D method ensures an opaque “inspection” through the colon loops.
Virtual endoscopy. This concerns a 3D reconstruction method in which the inner surface of hollow organs is displayed in the sense of an endoluminal view. This enables even the “inner” surface of hollow organs, in particular the intestinal surface, to be displayed virtually. This technique is applied, for example, in virtual endoscopy of the colon and, because of the high resolution that can be attained, even permits the detection of very small colon polyps from which colorectal carcinomas result according to the current state of knowledge. Detecting these polyps early can prevent the development of carcinoma.
Moreover, a method for automatic computer-aided detection (CAD) of colon polyps based on a tomography data record is known per se, for example from WO 2005/031648 A2 (EP 1665163 A2). The field of application of the innovative computer-aided detection (CAD) will spread substantially in the coming years.